X-Git-Url: http://4ch.mooo.com/gitweb/?a=blobdiff_plain;f=16%2Fxw__%2Fmodex%2FTHREED.ASM;fp=16%2Fxw__%2Fmodex%2FTHREED.ASM;h=5ecd3ba3a0097f19c786ff7a095b4f9b279dcbe4;hb=47cdc66151d973d975d0e31fb8a786eb639bebdb;hp=0000000000000000000000000000000000000000;hpb=4b23f27092a9470a741e3a18261ad389fd1929db;p=16.git diff --git a/16/xw__/modex/THREED.ASM b/16/xw__/modex/THREED.ASM new file mode 100755 index 00000000..5ecd3ba3 --- /dev/null +++ b/16/xw__/modex/THREED.ASM @@ -0,0 +1,872 @@ +COMMENT / + Fixed-point math functions and 3D transforms + Copyright (c) 1993,94 by Alessandro Scotti +/ +WARN PRO +P386 +JUMPS +LOCALS + +INCLUDE MATH.INC + +PUBLIC tdFixedMul +PUBLIC tdGetNormal +PUBLIC tdRotate +PUBLIC tdGetSurfaceLight +PUBLIC tdSetLight +PUBLIC tdSetRotation +PUBLIC tdSetTranslation +PUBLIC tdTransform +PUBLIC tdTransformToImage +PUBLIC tdTransformLight +PUBLIC tdBackPlaneCull +PUBLIC tdSetPerspective + +;----------------------------------------------------------- +; +; Data segment +; +MATH_DATA SEGMENT USE16 PARA PUBLIC 'DATA' + ASSUME ds:MATH_DATA + +INCLUDE SINCOS.INC ; Fixed 8:24 sin/cos table + +XRotation TPOINT <> ; 3x3 rotation matrix +YRotation TPOINT <> +ZRotation TPOINT <> + +Translation TPOINT <> ; Translation vector + +Light TPOINT <> ; Light vector +AmbientLight DW 00 ; Ambient light + +XScale DD 10000h ; Scaling factor for X coordinate +YScale DD 10000h ; Scaling factor for Y coordinate +PerspectiveDistance DD 20000000h + +MATH_DATA ENDS + +;----------------------------------------------------------- +; +; Code segment +; +MATH_TEXT SEGMENT USE16 PARA PUBLIC 'CODE' + ASSUME cs:MATH_TEXT, es:NOTHING, fs:NOTHING + +tdSetPerspective PROC PASCAL FAR + ARG Perspective:DWORD, \ + ScaleX:DWORD, \ + ScaleY:DWORD + USES ds + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + mov eax, [Perspective] + mov [PerspectiveDistance], eax + mov eax, [ScaleX] + mov [XScale], eax + mov eax, [ScaleY] + mov [YScale], eax + + ret +tdSetPerspective ENDP + + +;----------------------------------------------------------- +; +; Sets the rotation matrix. +; +; Input: +; RX = X-axis rotation angle +; RY = X-axis rotation angle +; RZ = X-axis rotation angle +; Output: +; none +; +tdSetRotation PROC PASCAL FAR + ARG RX:WORD, \ + RY:WORD, \ + RZ:WORD + USES ds, si, di + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + mov bx, [RZ] + mov si, [RY] + mov di, [RX] + shl bx, 2 + shl si, 2 + shl di, 2 + + push ebp ; We use EBP as a scratch register + +; Set X rotation + mov eax, tblCos[bx] + imul tblCos[si] + mov [XRotation.X], edx + + mov eax, tblSin[bx] + imul tblCos[si] + mov [XRotation.Y], edx + + mov eax, tblSin[si] + sar eax, 8 ; Convert fixed 8:24 to fixed 16:16 + mov [XRotation.Z], eax + +; Set Y rotation + mov eax, tblCos[bx] + imul tblSin[si] ; EDX:EAX = fixed 16:48 + shrd eax, edx, 24 ; EAX = fixed 8:24 + imul tblSin[di] ; EDX:EAX = fixed 16:48 + mov ebp, eax + mov ecx, edx + mov eax, tblSin[bx] + imul tblCos[di] + add eax, ebp + adc edx, ecx ; EDX:EAX = fixed 16:48 + neg edx + mov [YRotation.X], edx + + mov eax, tblSin[bx] + imul tblSin[si] + shrd eax, edx, 24 + imul tblSin[di] + mov ebp, eax + mov ecx, edx + mov eax, tblCos[bx] + imul tblCos[di] + sub eax, ebp + sbb edx, ecx + mov [YRotation.Y], edx + + mov eax, tblCos[si] + imul tblSin[di] + mov [YRotation.Z], edx + +; Set Z rotation + mov eax, tblCos[bx] + imul tblSin[si] + shrd eax, edx, 24 + imul tblCos[di] + mov ebp, eax + mov ecx, edx + mov eax, tblSin[bx] + imul tblSin[di] + sub eax, ebp + sbb edx, ecx + mov [ZRotation.X], edx + + mov eax, tblSin[bx] + imul tblSin[si] + shrd eax, edx, 24 + imul tblCos[di] + mov ebp, eax + mov ecx, edx + mov eax, tblCos[bx] + imul tblSin[di] + add eax, ebp + add edx, ecx + neg edx + mov [ZRotation.Y], edx + + mov eax, tblCos[si] + imul tblCos[di] + mov [ZRotation.Z], edx + + pop ebp ; Restore EBP + + ret +tdSetRotation ENDP + +;----------------------------------------------------------- +; +; Sets the translation vector. +; +; Input: +; TV = pointer to translation vector +; Output: +; none +; +tdSetTranslation PROC PASCAL FAR + ARG TV:DWORD + USES ds, es, di + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + les di, [TV] + mov eax, es:[di].X + mov [Translation.X], eax + mov eax, es:[di].Y + mov [Translation.Y], eax + mov eax, es:[di].Z + mov [Translation.Z], eax + + ret +tdSetTranslation ENDP + +;----------------------------------------------------------- +; +; Transforms an array of TPOINT. +; +; Input: +; Source = pointer to source array of TPOINT +; Dest = pointer to destination array of TPOINT +; Count = number of entries to transform +; Output: +; none +; +tdTransform PROC PASCAL FAR + ARG Source:DWORD, \ + Dest:DWORD, \ + Count:WORD + LOCAL Adjust:DWORD + USES ds, si, es, di, fs + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + lfs si, [Source] + les di, [Dest] + + ALIGN DWORD +@@Loop: +; Transform Z coordinate + mov eax, fs:[si].X + imul [ZRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, fs:[si].Y + imul [ZRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, fs:[si].Z + imul [ZRotation.Z] + add eax, ecx + adc edx, ebx + mov ebx, eax + shrd eax, edx, 16 + add eax, [Translation.Z] ; EAX = new Z coord (fixed 16:16) + mov es:[di].Z, eax +; Get perspective factor + mov ebx, [PerspectiveDistance] + sub eax, ebx + neg eax ; EAX = PD - Z + xor edx, edx + shld edx, eax, 16 + shl eax, 16 + idiv ebx ; EAX = fixed 16:16 result + mov [Adjust], eax + +; Transform X coordinate + mov eax, fs:[si].X + imul [XRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, fs:[si].Y + imul [XRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, fs:[si].Z + imul [XRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + add eax, [Translation.X] + imul [Adjust] + shrd eax, edx, 16 + mov es:[di].X, eax + +; Transform Y coordinate + mov eax, fs:[si].X + imul [YRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, fs:[si].Y + imul [YRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, fs:[si].Z + imul [YRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + add eax, [Translation.Y] + imul [Adjust] + shrd eax, edx, 16 + mov es:[di].Y, eax + + add si, SIZE TPOINT + add di, SIZE TPOINT + dec [Count] + jnz @@Loop + + ret +tdTransform ENDP + +;----------------------------------------------------------- +; +; Transforms an array of TPOINT into an array of TIMAGEPOINT. +; +; Input: +; Source = pointer to source array of TPOINT +; Dest = pointer to destination array of TIMAGEPOINT +; Count = number of entries to transform +; DeltaX = translation distance for the X coordinate +; DeltaY = translation distance for the Y coordinate +; Output: +; the maximum Z value +; +tdTransformToImage PROC PASCAL FAR + ARG Source:DWORD, \ + Dest:DWORD, \ + Count:WORD, \ + DeltaX:WORD, \ + DeltaY:WORD + LOCAL Adjust:DWORD, \ + Max:DWORD + USES ds, si, es, di, fs + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + lfs si, [Source] + les di, [Dest] + mov [Max], 80000000h + +@@Loop: +; Check max Z + mov eax, fs:[si].Z + cmp eax, [Max] + jle @@1 + mov [Max], eax +@@1: + +; Transform X coordinate + mov ax, WORD PTR fs:[si].X[2] + add ax, [DeltaX] + mov es:[di].IX, ax + +; Transform Y coordinate + mov ax, WORD PTR fs:[si].Y[2] + add ax, [DeltaY] + mov es:[di].IY, ax + + add si, SIZE TPOINT + add di, SIZE TIMAGEPOINT + dec [Count] + jnz @@Loop + + mov eax, [Max] + shld edx, eax, 16 + ret +tdTransformToImage ENDP + +;----------------------------------------------------------- +; +; Sets the light source. +; +; Input: +; Light = pointer to light vector +; Output: +; none +; +tdSetLight PROC PASCAL FAR + ARG L:DWORD + USES ds, es, di + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + les di, [L] + mov eax, es:[di].X + mov [Light.X], eax + mov eax, es:[di].Y + mov [Light.Y], eax + mov eax, es:[di].Z + mov [Light.Z], eax + + ret +tdSetLight ENDP + +;----------------------------------------------------------- +; +; Computes light intensity for an array of surfaces. +; +; Input: +; Normals = pointer to an array of surface normals +; Lights = pointer to an array of integer to be filled with +; light intensity +; Count = number of elements to transform +; Output: +; none +; +tdTransformLight PROC PASCAL FAR + ARG Normals:DWORD, \ + Lights:DWORD, \ + Count:WORD + USES ds, si, es, di, fs + + mov ax, SEG MATH_DATA + mov fs, ax + ASSUME fs:MATH_DATA + + lds si, [Normals] + les di, [Lights] + ASSUME ds:NOTHING + +; Intensity is given by the dot product between the Light vector and +; the surface normal +@@Loop: + mov eax, ds:[si].Z + imul [Light.Z] + mov ebx, eax + mov ecx, edx + mov eax, ds:[si].Y + imul [Light.Y] + add ebx, eax + adc ecx, edx + mov eax, ds:[si].X + imul [Light.X] + add eax, ebx + adc edx, ecx ; EDX:EAX = fixed 32:32 intensity + add dx, [AmbientLight] + test dx, dx + jg @@1 + xor dx, dx ; Return 0 for no light +@@1: + mov es:[di], dx + inc di + inc di + add si, SIZE TPOINT + dec [Count] + jnz @@Loop + + ASSUME fs:NOTHING + ret +tdTransformLight ENDP + +;----------------------------------------------------------- +; +; Returns the light value given the normal to a surface. +; +; Input: +; Normal = pointer to TPOINT surface normal vector +; Output: +; AX = light intensity (>=0) +; Notes: +; the normal is rotated according to the current setting. +; +tdGetSurfaceLight PROC PASCAL FAR + ARG Normal:DWORD + USES ds, esi, es, di + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + les di, [Normal] + +; Transform Z coordinate + mov eax, es:[di].X + imul [ZRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, es:[di].Y + imul [ZRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, es:[di].Z + imul [ZRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + imul [Light.Z] + shrd eax, edx, 16 + mov esi, eax + +; Transform X coordinate + mov eax, es:[di].X + imul [XRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, es:[di].Y + imul [XRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, es:[di].Z + imul [XRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + imul [Light.X] + shrd eax, edx, 16 + add esi, eax + +; Transform Y coordinate + mov eax, es:[di].X + imul [YRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, es:[di].Y + imul [YRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, es:[di].Z + imul [YRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + imul [Light.X] + shrd eax, edx, 16 + add eax, esi + shr eax, 16 + +; Add ambient light + add ax, [AmbientLight] + test ax, ax + jge @@Exit + xor ax, ax + +@@Exit: + ret +tdGetSurfaceLight ENDP + +;----------------------------------------------------------- +; +; Rotates an array of TPOINT. +; +; Input: +; Source = pointer to source array of TPOINT +; Dest = pointer to destination array of TPOINT +; Count = number of entries to transform +; Output: +; none +; +tdRotate PROC PASCAL FAR + ARG Source:DWORD, \ + Dest:DWORD, \ + Count:WORD + USES ds, si, es, di, fs + + mov ax, SEG MATH_DATA + mov ds, ax + ASSUME ds:MATH_DATA + + lfs si, [Source] + les di, [Dest] + +@@Loop: +; Transform Z coordinate + mov eax, fs:[si].X + imul [ZRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, fs:[si].Y + imul [ZRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, fs:[si].Z + imul [ZRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + mov es:[di].Z, eax + +; Transform X coordinate + mov eax, fs:[si].X + imul [XRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, fs:[si].Y + imul [XRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, fs:[si].Z + imul [XRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + mov es:[di].X, eax + +; Transform Y coordinate + mov eax, fs:[si].X + imul [YRotation.X] + mov ecx, eax + mov ebx, edx + mov eax, fs:[si].Y + imul [YRotation.Y] + add ecx, eax + adc ebx, edx + mov eax, fs:[si].Z + imul [YRotation.Z] + add eax, ecx + adc edx, ebx + shrd eax, edx, 16 + mov es:[di].Y, eax + + add si, SIZE TPOINT + add di, SIZE TPOINT + dec [Count] + jnz @@Loop + + ret +tdRotate ENDP + +tdFixedMul PROC PASCAL FAR + ARG F1:DWORD, \ + F2:DWORD + + mov eax, [F1] + imul [F2] + shr eax, 16 + + ret +tdFixedMul ENDP + +;----------------------------------------------------------- +; +; Returns in EAX the square root of EDX:EAX. +; +subSqrt PROC NEAR + push esi + push edi + + add eax, eax + adc edx, 0 + mov eax, edx ; Just discard the low bits + + mov esi, eax + xor edi, edi + shld edi, esi, 16 + shl esi, 16 +@@Loop: + mov ebx, eax + mul eax + add eax, esi + adc edx, edi + shrd eax, edx, 1 + shr edx, 1 + div ebx + cmp eax, ebx + jne @@Loop + +; Adjust EAX + shl eax, 8 + + pop edi + pop esi + ret +subSqrt ENDP + +;----------------------------------------------------------- +; +; Finds the unitary normal to a given surface. +; +; Input: +; Dest = pointer to TPOINT (vector) result +; P1, P2, P3 = pointer to TPOINT points on surface +; Output: +; none +; Notes: +; the normal is given by the cross-product between (P3-P1) and +; (P2-P1), so its orientation depends on the parameters order. +; +tdGetNormal PROC PASCAL FAR + ARG Dest:DWORD, \ + P1:DWORD, \ + P2:DWORD, \ + P3:DWORD + LOCAL V1:TPOINT, \ + V2:TPOINT, \ + N:TPOINT + USES ds, si, es, di + +; Get vector V1 + lds si, [P1] + les di, [P3] + mov eax, es:[di].X + sub eax, ds:[si].X + mov [V1.X], eax + mov eax, es:[di].Y + sub eax, ds:[si].Y + mov [V1.Y], eax + mov eax, es:[di].Z + sub eax, ds:[si].Z + mov [V1.Z], eax + +; Get vector V2 + les di, [P2] + mov eax, es:[di].X + sub eax, ds:[si].X + mov [V2.X], eax + mov eax, es:[di].Y + sub eax, ds:[si].Y + mov [V2.Y], eax + mov eax, es:[di].Z + sub eax, ds:[si].Z + mov [V2.Z], eax + +; Get normal vector (V1 x V2) + mov eax, [V1.Z] + imul [V2.Y] + mov ebx, eax + mov ecx, edx + mov eax, [V1.Y] + imul [V2.Z] + sub eax, ebx + sbb edx, ecx + shrd eax, edx, 16 + mov [N.X], eax + + mov eax, [V1.X] + imul [V2.Z] + mov ebx, eax + mov ecx, edx + mov eax, [V1.Z] + imul [V2.X] + sub eax, ebx + sbb edx, ecx + shrd eax, edx, 16 + mov [N.Y], eax + + mov eax, [V1.Y] + imul [V2.X] + mov ebx, eax + mov ecx, edx + mov eax, [V1.X] + imul [V2.Y] + sub eax, ebx + sbb edx, ecx + shrd eax, edx, 16 + mov [N.Z], eax + +; Get normal length + mov eax, [N.X] + imul eax + mov ebx, eax + mov ecx, edx + mov eax, [N.Y] + imul eax + add ebx, eax + adc ecx, edx + mov eax, [N.Z] + imul eax + add eax, ebx + adc edx, ecx ; EDX:EAX = N.X*N.X + N.Y*N.Y + N.Z*N.Z + call subSqrt ; EAX = normal length + mov ebx, eax + +; Adjust vector and save it + les di, [Dest] + mov eax, [N.X] + cdq + shld edx, eax, 16 + shl eax, 16 + idiv ebx + mov es:[di].X, eax + mov eax, [N.Y] + cdq + shld edx, eax, 16 + shl eax, 16 + idiv ebx + mov es:[di].Y, eax + mov eax, [N.Z] + cdq + shld edx, eax, 16 + shl eax, 16 + idiv ebx + mov es:[di].Z, eax + + ret +tdGetNormal ENDP + +TPOLY STRUC + Vtx DW 4 DUP(?) +TPOLY ENDS + +;----------------------------------------------------------- +; +; Performs surface removal on an array of polygons. +; +; Input: +; Poly = pointer to an array of TPOLY +; Vertex = pointer to an array of TPOINT +; Dest = pointer to an array of integer +; Count = number of polygons to check +; Step = size of TPOLY structure +; Output: +; if the n-th polygon is invisible the n-th entry of the +; Dest array is set to -1, other entries are not modified +; (so it's possible to use the Light array for Dest, because +; the light intensity is always >= 0) +; +tdBackPlaneCull PROC PASCAL FAR + ARG Step:WORD, \ + Poly:DWORD, \ + Vertex:DWORD, \ + Dest:DWORD, \ + Count:WORD + USES ds, si, es, di, fs + ASSUME ds:NOTHING + + mov ds, WORD PTR Vertex[2] + les di, [Poly] + mov fs, WORD PTR Dest[2] + +@@Loop: + mov ax, es:[di].Vtx[2] ; Index of 2nd vertex + shl ax, 2 + mov bx, ax + shl ax, 1 + add bx, ax ; BX = index*SIZE TPOINT + add bx, WORD PTR [Vertex] ; BX = offset of 2nd vertex + mov ax, es:[di].Vtx[4] ; Index of 3rd vertex + shl ax, 2 + mov si, ax + shl ax, 1 + add si, ax + add si, WORD PTR [Vertex] ; SI = offset of 3rd vertex + mov ecx, ds:[si].X + sub ecx, ds:[bx].X ; ECX = V3.X-V2.X + mov edx, ds:[si].Y + sub edx, ds:[bx].Y ; EDX = V3.Y-V2.Y + mov ax, es:[di].Vtx[0] ; Index of 1st vertex + shl ax, 2 + mov si, ax + shl ax, 1 + add si, ax + add si, WORD PTR [Vertex] ; SI = offset of 1st vertex + mov eax, ds:[si].X + sub eax, ds:[bx].X ; EAX = V1.X-V2.X + mov esi, ds:[si].Y + sub esi, ds:[bx].Y ; ESI = V1.Y-V2.Y + imul edx + mov ebx, eax + xchg ecx, edx ; ECX:EBX = (V1.X-V2.X)*(V3.Y-V2.Y) + mov eax, esi + imul edx ; EDX:EAX = (V1.Y-V2.Y)*(V3.X-V2.X) + sub eax, ebx + sbb edx, ecx + jl @@Next ; Polygon is visible + mov bx, WORD PTR [Dest] ; FS:BX -> current Dest entry + mov WORD PTR fs:[bx], -1 ; Remove polygon +@@Next: + add WORD PTR [Dest], 2 ; Next entry for dest + add di, [Step] ; Next polygon + dec [Count] + jnz @@Loop + + ret +tdBackPlaneCull ENDP + +MATH_TEXT ENDS +END